Contrastive Analysis Of Particle Distribution Between Floor Heating And Readiator Heating Room

Human beings spend about 80% of their life indoors and more and more epidemiology research indicated that the indoor particles pollution has positive relevance with disease incidence rate and the mortality rate, especially the inhalable particles with less than 10μm of diameter. Therefore, the density distribution of indoor particles in the air is especially important to human health.In this article, I choose a north bedroom in Taiyuan as my object, established the physical and the mathematical models of indoor air flow on two different heating ways, the floor heating and the radiator heating, and the 3-dimensional indoor air velocity and the temperature distribution is numerical simulated with the k -εequation and the SIMPLE algorithm. At the same time, using the particle trajectory model, take the particles which diameters are 7.5μm, 3.5μm and 0.4μm for instant, I simulate the mass concentration distributions of indoor particles which enter the room from the outside and the ground deposition particles which suspend secondly in the room using floor heating and the radiator heating . The test to the particles counting density distribution in a room using floor heating, showed that the result of the test was consistent with the numerical simulation. And then we can get the following conclusion:1,The indoor air flow has a strong influence on the particles whose diameters like that. The particles are apt to adhere to air current.2,Heating mode has a strong influence on the particles whose diameters like that. When difference of temperature is too large in indoor, particles distribute with high concentration. If the particles have the same diameter, the concentration of those particles which are close to the region of floor heating and radiator heating is higher than other particles.3,The particles which are from outside and the deposition particles which suspend secondly have an important influence on the indoor particles intent. In the room using floor heating, the concentration of the particles from the north exterior window near the north exterior window is higher than other regions, and the concentration of the deposition particles which suspend secondly near the inner wall is higher than other regions. In the room using radiator heating, the concentration of the particles both from exterior window and the second suspending is higher in the region near the radiator than other regions. In the center region of the room along the direction from north to south, the distribution of concentration of particles in the room using floor heating and the room using radiator heating is not significant different.4,The numerical simulation and the experimental study demonstrated that the particles with 7.5μm diameter by gravity, whose concentration of particles in the direction of height descend faster than the particles with 3.5μm, 0.4μm diameter.5,In the situation of certain difference of temperature in indoor, the particles with 0.4μm diameter is obvious influenced by thermophoretic and the Brownian Motion . The concentration is homogeneous in the direction of height.